Tension device for electric conductors



(No Model.) l

l E J. C. LOVE..

TENSION DEVIGE POE ELECTRIC GONDUGTURS.

Patented Dec. 26, 189s:

UNITED STATES PATENT OFFICE.

JOHN C. LOVE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR' TO THE LOVE ELECTRIC TRACTION COMPANY, OF CHICAGO, ILLINOIS.

TENSION DEVICE FO'R ELECTRIC CONDUCTORS.

SPECIFICATION forming part of Letters Patent No. 511,345, dated December 26, 1893.

Application filed January 21, 1893. Serial No. 459i233f (N 11105010 This invention relates to that class of elec-v tric traction systems in which the current is supplied through conductors leading from a generator or source of electric supply and arranged parallel with the tram rails of a road, and is especially applicable to underground systems wherein the conductor or conductors are located within a slotted conduit, and the zo trolleys are supported by a bar suspended from a car or vehicle and traveling in a slot of said conduit. In such systems it is important that the conducting wires be maiutained parallel with the slot of the conduit, z5 or practically so, to insure that the contact device or trolley shall travel evenly and smoothly in contact therewith, but difliculty has heretofore been found in preserving such parallelism of the conducting wires with the 3o slot of a conduit, owing partly to the expansion and contraction of the conductors under changes of temperature.

One object of this invention is to maintain a constant longitudinal strain or tension upon 3 5 the metal wire or strand forming the conductor, thereby avoiding sag or droop of said conductor between its points of support, and further to automatically take up or compensate for slack in such conducting wires due to 4o changes in temperature.

With this and minor objects in view my invention consists in the matters to be hereinafter described, and then particularly set forth in the claims.

In the accompanying drawings: Figure 1- isa verticallongitudinal section taken through a conduit, and illustrating one form of apparatus for carying out my invention. Fig. 2.- is a bottom plan view of the apparatus illus- 5o strated in Fig. l. Fig. 3- is a side elevation, on a larger scale of the tension device for the conducting wire. Fig. 4 is a transverse section, illustrating, in end view, the parts seen in Fig. 3. Fig. 5- is a longitudinal section of a telescoping orcompensating coupling for two sections of the conducting wire.

That form or construction of mechanical devices which I have selected to illustrate my invention is one in which said invention has been embodied in practical operative form, 6o but it will be understood that I do not confine myself to the exact details of construction shown therein, as my said invention is capable of embodiment in other forms and constructions of details not described in detail herein.

One part of my invention relates to the straining or tensioning ofthe conductor wires in the conduit to maintain them in horizontal alignment, or practically so, with the slot 7o rail, thereby avoiding, wholly or in part, the sag of thev wire between its points .of support. In carrying out this part of my invention the wire forming the conductor or conductors is preferably, though not necessarily, strung in sections of greater or less length, say from one hundred to one thousand feet; the length of the sections being determined by the particular circumstances of the case. At the end of each section of the conductor a clip or gripping device is located, said clip or gripping device being connected to some point having sufficient resistance to movement to sustain the desired tension, and the conductor is put under tension by any suitable mechanism. This results in taking up the sag of the conductor between its points of support. In sections of great length the gripping devices might be used at required intervals, thus adapting this part of 9o junction with the gripping devices before ref erred to.

Referring now to the drawings for a fuller understanding of the features above mentioned, the conduit A may be constructed in any approved manner, containing the customary yokes A A2 and A3 at intervals to support the slot rails, not shown. The yokes are provided with horizontal supporting rods a arranged parallel with each other side by side, and insulators B are mounted to slide longitudinally upon these rods, said insulators being provided with depending jaws or clips Z) to grasp and hold the conductor C.

As before stated, the conductor or conductors are preferably arranged in sections of greater or less length, the drawings herein being intended to represent the junction of two sections,1 and 2, but as the respective ends of all the sections are alike as to detail, the illustration of one end of section l, is deemed sufficient. The arrangement I have adopted for the adjacent ends of two adjacent sections, l and 2, is here illustrated as including yokes A', A2, A3 and a fourth one,not shown,between the outer two, A A2 of which my tension devices are located, a telescoping coupling D, to be presently described, being located between the inner two A2 and A3 of said four yokes, and the whole of said devices being suspended from supporting or guide rods a a extending through the four yokes mentioned and secured rigidly to the yokes to prevent end wise movement thereof.

For the purposes of this application I have illustrated the straining devices, and yielding tension devices as a single assemblage ofinechanical parts comprising a spring or springs E, here shown as compression springs resting at one end against an abutment or abutments E', a longitudinally movable block F bearing against the other end of the spring, a clip or gripping device G connected with one or more insulators B by which it is suspended from the supporting rods a and an inclined or oblique coupling rod f attached at one end to said movable block F and at the other end to said clip G. The abutment or abutments E are carried by the supporting rods a and are adjustably attached thereto in any preferred manner. The springs E (two being shown herein, one for each rod c) surround the supporting rods a bearing at one end against the abutment E thereon, their opposite ends affording a yielding support for the sliding or movable block F which is also mounted on said supporting rods a and has free movement thereon, longitudinally. The coupling rod f is attached to the block F midway between the points of support of the latter upon the rods a, and is preferably adjustable lengthwise to admit of 1ncreasing or decreasing the distance between the block F and the gripping device G.. As shown, the upper end of the coupling rodf asses through a longitudinal aperture 1n the block F, and is threaded at its end to receive a nut f by means of which the rod may be drawn a greater or less distance through the block. The particular means, however, for effecting this adjustment is immaterial, as a turn buckle, or any other equivalent device might be used. An insulating coupling f2 of any approved form, is interposed between the block F and the conductor clip G, said coupling forming, in this instance, a part ot' the coupling rodf, as shown.

The clip or gripping device G, shown comprises two longitudinally disposed members g g arranged side by side, one of said members, g being provided with laterally projecting bolts g2 which project through slots or openings in the other member g', and are fitted with clamping nuts g3, by means of which the said members or jaws of the clip may be drawn together to clamp the conducting wire C tightly between them. The member or jaw g is provided with one or more upward extensions g4, two being shown, each of which is connected rigidly with an insulator block B, said blocks B being supported by and adapted to move longitudinally upon the parallel supporting rods a..

The insulators B and block F, it will be seen are designed to move or slide longitudinally upon the supporting rods a, and may be all of the form shown, consist-ingof a rectangular body having the longitudinal or side edges thereof grooved to receive said supporting rods, or of any other preferred form capable of the same function. For instance, in lieu of the pair of parallel supporting rods a, a single rod may be used, angular in cross section, the insulators and block F being then formed with an angular longitudinal passage IOO to receive said rod, so that they may slide but v not rotate thereon.

To avoid endwise movement or slipping of the conductor C in the jaws of the clip G it may be soldered therein, after the jaws have been tightly clamped upon it.

From the foregoing it will be understood that each conductor C of each section l, 2, &c., is not only subjected to opposite endwise strain by the described devices secured to the opposite ends of the respective sections, but that by the employment of springs, weights or other equivalent yielding connections E, in connection with said devices, as described, the tension upon said conductor remains practically the same under varying temperatures. A yielding tension device at only one end of each section of the conductor would be practically operative, though I prefer the arrangement herein shown, especially in sections of great length, as by this arrangement each tension device is required to compensate for but half of the expansion or contraction of its particular section.

Another part of my invention relates to means for coupling the adjacent ends of the respective sections wherebya continuous surface is presented for the travel of the trolleys through the adjacent ends of the conductors IIO which my invention has been embodied in.

practical operative form, but do not confine myself to the mechanical details therein. The coupling D is suspended from the supporting rods a by an insulator B, said coupling and insulator being located centrally between the yokes A2 and A3 of the conduit A. Other insulators B are arranged between said yokes, their clips b engaging the free ends of the conductors C of the respective sections 1 and 2, one of said insulators beingv located between the yoke A2 and the adjacent end of the coupling D, and the otherbetween the other end of said coupling-and the yoke A3, as shown. The coupling D is composed of two tubular end sections d and an interposed central section d to which they are secured, as shown, said central or nontubular section d being grasped by the jaws of the clip b of insulator B. The end sections d are of such diameter interiorly as to permit of the free endwise movement within them of the ends of the conductor sections C but to prevent lateral play thereof, and are preferably beveled or chamfered at their outer ends to present al practically unbroken surface for the travel of the trolleys. To provide against a possible interruption of the current on the conductor C incidental to the employment of the coupling here described, the clips b of the insulators B adjacent to said coupling are provided with eyes or loops b to receive a short section of wire D', as shown, the current then passing through the clips b of said insulators and through said wire D. This wire D is clamped tightly within the eye b of one of the clips b but left free to move longitudinally within the other, to admit of expansion or contraction of said wire and the conductor C withoutdisturbing the continuity of the line.

l. rThe combination with a conductor and insulators arranged at intervals along the conductor and secured to the same, said insulators being free to move upon their supports longitudinally with the conductor of a tension device having immediate connection with said conductor and exerting a constant longitudinal strain thereon, substantially as described.

2. The combination with a conductor'and insulatorsarranged at intervals and secured to the conductor, said insulators being free to move longitudinally with the conductor of a tension spring having immediate connection with the conductor to maintain a constant longitudinal strain thereon, substantially as described.

3. The combination with a slotted conduit, insulators supported to move longitudinally therein, and a conductor secured to said insulators, of a tension spring applied between a stationary part of the conduit and said conductor independently of the insulators and maintaining a constant strain thereon, substantially as described.

4. The combination with a conductor consisting of a plurality of separate sections free to move longitudinally with relation to their supports, of an automatic tension device connected with each section and maintaining a constant strain thereon to compensate `for contraction or expansion therein, and a telescopic tubular coupling within which the adjacent ends of adjacent sections of the conductor are inserted, substantially as described.

5. The combination of a conductor consisting of a plurality of separate sections free to move longitudinally with relation to their supports, automatic tension devices connected with each end lof each section and maintaining a constant strain thereon in opposite directions and a telescoping coupling connecting adjacent sections, substantially as described.

6. The combination with the yokes of a conduit, a longitudinal guide bar or bars connected thereto, insulators mounted to slide IOO thereon, and a sectional conductor carried l by said insulators, of means independent of said insulators for maintaining the conductor sections under tension, substantially as described. r

7. A tension device for electric conductors comprising a sliding block an abutment, a spring applied between the said abutment, and the sliding block, a clip supporting the conductor, and an adjustable coupling rod connecting said clip with the said block, substantially as described.

8. The combination with a conductor free to move endwise relatively to its supports, of a tension device comprising a sliding insulator for supporting the end of the conductor, a guide rod or rods parallel with the conductor for the insulator, on which the latter is adapted to slide, a supporting clip for the conductor attached to said insulator, a sliding block movable parallel with the conductor, an oblique coupling rod connected with the said sliding block and with the clip, and a spring applied to the sliding block to maintain tension on the conductor, substantially as described.

9. The combination with a conductor free to move endwise relatively to its supports,of a tension device comprising an insulator, a clip for supporting the conductor attached t-o said insulator, a guide rod or rods forthe said insulator arranged parallel with the -conductor, a sliding block, a 'guide rod or rods there-` for, arranged parallel with the conductor, an

oblique coupling rod connecting the clip with said sliding block an abutment secured to said guide rod or rods, and a spring or springs applied between the sliding block and the abutment, for maintaining tension on the conductor, substantially as described.

10. The combination with a conductor free to move endwise relatively to its supports, of a tension device comprising a guide rod or rods arranged parallel with the conductor an insulator sliding thereon, a supporting clip attached to said insulator, a sliding block and abutment on the guide rod or rods, a spring applied between the sliding block and the abutment, and an oblique coupling rod connecting the clip with the sliding block, substantially as described.

ll. The combination with a conductor free to move endwise relatively to its supports, of a tension device comprising an insulator movable parallel with the conductor, a supporting clip attached to the wire and to said insulator a sliding block movable parallel with the conductor, a coupling rod connecting the sliding block with the clip, said .rod containing an insulating section, and a spring applied to the sliding block to maintain tension on the conductor, substantially as described.

l2. The combination with the yokes of a slotted conduit,and aconductor therein movable endwise relatively to its support, of guide rods attached to the yokes,an insulator sliding on said guide rods, a clip for supporting the conductor attached to said insulatora sliding block mounted ou said guide rods, an oblique coupling rod connecting the clip with the said sliding block, and a spring applied between the said sliding block and an adjacent stationary part, for maintaining tension on the conductor, substantially as described.

13. A tension-device forelectric conductors comprising a supporting clip a sliding block, a coupling rod connecting the said clip with the sliding block, an abutment adjustably connected with its support, and a spring be' tween the sliding block and abutment for maintaining tension on the conductor, substantially as described.

14E. The combination with the yoke of a slotted conduit, and a conductor therein consisting of separate sections movable endwise relatively to their supports, of guide-rods attached to the said yokes, insulators sliding on the rods, clips for supporting the ends of the conductor attached to the said insulators, sliding blocks on said guide rods, coupling rods connecting said sliding blocks with the clips, springs applied to the sliding blocks to maintain tension on the conductor sections, and a telescopic coupling piece connecting the ends of the conductor, substantially as described.

15. The combination with the yokes of a conduit and a conductor, of a guide rod or rods attached to the yokes, an insulator sliding on the4 guide rod or rods a clip for supporting the conductor attached to said insulator, a sliding block on said guide rod or rods, a coupling rod connecting the sliding block with the clip, an abutment adj ustably mounted on said guide rod or rods, and a spring applied between said abutment and sliding block to maintain tension on the conductor, substantially as described.

In testimony that I claim the foregoing as my invention I affix my signature in presence of two witnesses.

JOHN C. LOVE. Witnesses:

C. A. NEALE, CHAs. A. ONEILL. 

